Most painful thing I ever saw happen was to my brother. We were tubing on a lake when it was white capping. He was in the tube and his friend was driving the boat. He hit a cap and bounced off the tube came back down hard and bounced even higher. Slack got in the line and when he landed from the second bump his leg got caught in the line, boat pulled the slack out and it gave him rope burn in his calf....that was HALF AN INCH DEEP!!!!!!!!!! He just floated in the water because he was sure his leg was gone and he didn't want to see it. I still cringe for him when I think about it and that mutha effer is dead to me.